Speaker



Feb. 8, 1966 E. A. HEPPNER 3,234,339

SPEAKER Filed April 18, 1962 2 Sheets-Sheet 1 IN VENTOR.

Feb. 8, 1966 E. A. HEPPNER 3,234,339

SPEAKER Filed April 18, 1962 2 Sheets-Sheet 2 O o O 6L H; X i i H j [576 5 INVENTOR.

United States Patent Ofiice 3,234,333 Patented Feb. 8, 1966' 3,234,339 SPEAKER Elmore A. Heppner, Round Lake, 11]., assignor to Heppner Manufacturing Co., a corporation of Illinois Filed Apr. 18, 1962, Ser. No. 188,319 3 Claims. (Cl. 179-1155) This invention relates to an electrical transducer and, more particularly, to a new and novel loudspeaker construction.

It is a general object of the present invention to produce a new and improved transducer for converting electrical energy into sound.

It is a more particular object of the invention to produce an electrical transducer in the form of a loudspeaker constructed and designed to occupy a minimum space, particularly in depth, while still maintaining the ability of the loudspeaker to reproduce sounds faithfully and accurately.

It is yet a further object of the invention to produce a loudspeaker which may be constructed in a form to utilize an elongated strip of nonferrous metal as the armature of the transducer, which strip is suspended between two elongated bar magnets providing the magnetic field in which the strip will vibrate when subjected to an electrical current.

Other and further objects of the invention will be readily apparent from the following description and drawings in which:

FIG. 1 is a top plan view of a loudspeaker embodying the invention;

FIG. 2 is a View like FIG. 1 with the loudspeaker cone removed;

FIG. 3 is a view of the rear side of the loudspeaker;

FIG. 4 is a vertical sectional view taken along line 44 of FIG. 3;

FIG. 5 is a view of the base plate illustrating a modified form of construction; and

FIG. 6 is a further view of the modified form taken along line 66 of FIG. 5.

While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail an embodiment of the invention together with a modification thereof, with the understanding that the present disclosure is to be con sidered as an exemplification of the principles of the invention and is not intended to limit the invention to the embodiments illustrated. The scope of the invention will be pointed out in the appended claims.

Referring now to the drawings, there is shown a loudspeaker 10 having a rectangular base plate 11 provided with a rectangular opening 12 therein in which two bar magnets 13 and 14 are mounted in parallel relationship with the opposite poles of the magnets being adjacent each other. Thus, north and south poles are provided at each end of the opening.

The magnets are spaced one from the other to provide an elongated slot 15 therebetween in which slot is movably mounted an armature in the form of a strip of nonferrous metal 16. Preferably copper is used for the armature, however, other nonferrous metals can also be used if desired.

The armature or strip 16 is suspended for movement in the slot 15 by a pair of springlike contacts 17 secured to the strip 16 at one end and to the plate 11 at the other end by means of bolts 18 suitably insulated by the insulation 19 from the base. The bolts 18, of course, also serve as terminals to be connected to a source of electrical power in the usual manner.

The strip 16 is provided with two finger portions 20 and 21 extending upwardly therefrom and secured in spaced relationship on opposite sides of the center portion of a loudspeaker cone 22 which is preferably fiat or inverted. The cone is secured by means of a gasket 23 to a basket 24, as of metal or plastic, mounted on the frame and carrying the cone. The outer extremities of the basket and cone assembly may be secured to a mounting plate 25 so that a speaker assembly may be secured in desired position.

In operation, electrical current is supplied to the terminals 18 and hence to the strip 16 thus causing the strip to move in the slot 15 toward and away from the mounting plate 25, such motion of the armature or strip being imparted to the cone by virtue of the connection thereto provided by the fingers 20 and 21. Movement of the cone in response to movement of the armature reproduces sound.

It will be noted that the present construction is a substantial departure from the normal circular voice coil type of loudspeaker construction and by virtue of the design illustrated, a loudspeaker can be constructed which is much shallower in depth front to back, and hence more adaptable to mounting in confined areas. At the same time, fidelity of reproduction is not sacrificed and, in fact, improved reproduction may often result.

A somewhat modified form of mounting means for the strip armature is shown in FIGS. 5 and 6 which illustrate a portion of a loudspeaker similar to that previously described in that there is provided a base plate 31 having a rectangular opening 32 therein, in which opening is mounted a pair of bar magnets 33 and 34. The magnets are spaced to provide therebetween a slot 35 in which an armature 36 is located. The armature is suspended on spring-like members for movement in the slot, the members comprising corrugated metal strips 37 secured at their centers to the strip 36 and at their outer extremities to terminal bolts 38 suitably insulated from the base 31. Members 37 extend across opening 32 at the upper and lower edges thereof. Other than the construction and arrangement of the spring-like mounting strips 37, the embodiment of FIGS. 5 and 6 is similar to the one previously described.

I claim:

1. A loudspeaker comprising: a frame, a pair of elongated magnets mounted in spaced parallel relationship in the frame to provide an elongated linearly extending narrow slot therebetween, an elongated strip of nonferrous metal forming an armature extending from substantially end to end of the slot, spring means carrying the armature and electrically connected thereto, said spring means being mounted on but electrically insulated from the frame, means including said spring means for connecting the armature at two spaced points to a source of electrical power to establish a circuit through said armature, a cone mounted on the frame and means connecting the cone to the armature.

2. A loudspeaker comprising: a frame, a pair of elongated magnets mounted in spaced parallel relationship in the frame to provide an elongated linearly extending narrow slot therebetween, an elongated strip of nonferrous metal forming an armature extending from substantially end to end of the slot, spring means carrying the armature and electrically connected thereto, said spring means being mounted on but electrically insulated from the frame, means including said spring means for connecting the armature at two spaced points to a source of electrical power to establish a circuit through said armature, a cone mounted on the frame and means for connecting the armature to the cone at two spaced points spaced on either side of the center of the cone.

3.: A loudspeaker comprising: a frame, a pair of elongated magnets mounted in spaced parallel relationship in the frame to provide an elongated linearly extending narrow slot therebetween, an elongated strip of nonferrous metal forming an armature extending from substantially end to end of the slot, a pair of corrugated metal strips secured to the frame and providing spring means movably supporting the armature in said slot,

a means electrically insulating the metal strips from the frame, a cone mounted on the frame, means connecting the armature to the cone, and means for connecting the metal strips to a source of electrical power.

References Cited by the Examiner UNITED STATES PATENTS OTHER REFERENCES Elements of Loudspeaker Practice, by N. W. Mc Lachlan, Oxford University Press, pages 28-31.

20 ROBERT H. ROSE, Primary Examiner. 

1. A LOUDSPEAKER COMPRISING: A FRAME, A PAIR OF ELONGATED MAGNETS MOUNTED IN SPACED PARALLEL RELATIONSHIP IN THE FRAME TO PROVIDE AN ELONGATED LINEARLY EXTENDING NARROW SLOT THEREBETWEEN, AN ELONGATED STRIP OF NONFERROUS METAL FORMING AN ARMATURE EXTENDING FROM SUBSTANTIALLY END TO END OF THE SLOT, SPRING MEANS CARRYING THE ARMATRUE AND ELECTRICALLY CONNECTED THERETO, SAID SPRING MEANS BEING MOUNTED ON BUT ELECTRICALLY INSULATE FROM THE FRAME, MEANS INCLUDING SAID SPRING MEANS FOR CONNECTING THE ARMATURE AT TWO SPACED POINTS TO A SOURCE OF ELECTRICAL POWER TO ESTABLISH A CIRCUIT THROUGH SAID ARMATURE, A CONE MOUNTED ON THE FRAME AND MEANS CONNECTING THE CONE TO THE ARMATURE. 